BEIJING — China’s National People’s Congress on Sunday approved a plan to abolish presidential term limits, making it possible for President Xi Jinping to stay in power indefinitely and cementing a dramatic shift in Chinese politics.

At Beijing’s Great Hall of the People, on the western edge of Tiananmen Square, 2,964 delegates cast their votes, with 2,958 in favor of the constitutional amendment, two against, and three abstentions and one invalid vote.

The ballot, which was largely symbolic, came two weeks after Communist Party-controlled media announcedthe proposal. It included other changes designed to put Xi and the party at the very heart of Chinese life.

It is the clearest evidence yet that Xi plans to rule beyond the end of this second term, in 2023, taking China back to the era of one-man rule just as it steps up its role in global politics.

“It means that Xi is now unquestionably a Leninist strongman,” Steve Tsang, director of the China Institute at SOAS University of London. Xi, unlike his predecessor, is not first among equals but “lord and master of them all,” he said.

Though state-controlled media insisted that the constitutional changes had “won the hearts of the people,” the news spurred a wave of public worry about a return to the despotic politics of the past.

“It’s a historic retrogression,” said Li Datong, a former editor of China Youth Daily, a state newspaper.

“Throughout history, only Chinese emperors and Mao Zedong had lifelong tenure until their deaths,” Li said. “And what came out of that was a disaster for the society and many painful lessons.”

The move marks an end to a system put in place by Deng Xiaoping in the 1980s to prevent the rise of another Mao, who was chairman of the Communist Party from before its accession to power in 1949 until his death in 1976.

“If the constitution of one nation can be amended by the most powerful person according to his or her will, the constitution is not a real constitution,” said He Weifang, a law professor at Peking University. “The legacy of Deng Xiaoping’s efforts to avoid lifelong presidency have been abolished completely.”

Though the power grab has earned Xi comparisons to leaders such as Turkey’s Recep Tayyip Erdogan and Russia’s Vladimir Putin, his vision for China is singular — and will have an impact well beyond China’s borders.

Since his ascendance in 2012, Xi has moved quickly to consolidate power at home and trumpet an ever-grander vision of China’s place in the world.

At a Communist Party congress last year, his signature theory — “Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era” — was enshrined in China’s constitution. He started his second five-year term with no clear successor.

Party media have since amped up the hagiography, casting Xi as the father of the nation and the man uniquely equipped to lead. What remains to be seen is how Xi’s new strongman status shapes governance on the ground.

Xi has built his presidency on a bold promise to “rejuvenate” China and put the country back at the center of the world. Now he must deliver, experts said.

“Everyone expects that this will make Xi Jinping a stronger, more decisive leader, but it’s also possible that he will need to justify this change by maintaining his popularity,” said Mary Gallagher, director of the Lieberthal-Rogel Center for Chinese Studies at the University of Michigan.

“That doesn’t bode well for difficult reforms ahead: Will the [Communist Party] be able to raise the retirement age? Enact a property tax?” she said. “A second-term president with nothing to lose might have been in a better position to enact these changes and accept the blame before stepping down.”

Tsang, of SOAS, said the constitutional change signaled a worrying trend: the elimination of dissenting views in policymaking.

“This shows he has now narrowed the scope of internal policy debates so much that no one dared to counsel him,” he said by email.

“If Xi is right, he will be more effective in getting his policies implemented,” Tsang said. “But if Xi gets it wrong on any major policy matter, God (or Marx) help China, for there will be no one else who can.”

Carl Minzner, a professor at Fordham Law School and the author of “End of an Era: How China’s Authoritarian Revival Is Undermining Its Rise,” said Sunday’s vote showed that the political norms that have governed Chinese politics for decades are coming undone.

“The risk now is: As those norms and institutions steadily erode, how much of the earlier instability could return?”